Application research on groundwater grouting treatment technology in the soft rock area of Mindong No.1 Mine

Abstract:

Mining water discharge and groundwater protection is at issue due to the limited water storage space in the goaf collapse zone due to the relatively soft overlying rock with high contents of clay in the south mining area of Mindong No.1 Mine. With analysis of the groundwater leakage causes， it was concluded that the overlying rock fractures produced by coal mining was the main source of groundwater leakage； meanwhile， the water channeling cracks in the overlying rock can be effectively blocked with artificial grouting via boreholes to block the groundwater discharge channel and curtain grouting reinforcement technology to seal off water channeling cracks in the roadway. Field application has proven that curtain grouting with in-hole screen pipes in the soft surrounding rock of the roadway to fully fill and reinforce the cracks in the soft surrounding rock is an important way to achieve “zero discharge” and groundwater protection of mining water in the mine through proper selection of the location of the grouting holes， spacing， grouting material and slurry ratio， borehole structure and drilling parameters according to the engineering geological conditions of the mining area.